TMG and Muscle Fatigue

TMG successfully detected fatigue, evident from reduced MVC,
by displaying impaired muscle displacement accompanied by
elevated PMT. TMG could be useful in establishing skeletal
muscle fatigue status without exacerbating the functional
decrement of the muscle.

In situations of muscle fatigue, or indeed musculoskeletal injury, it is impractical to assess muscle function through a measure
that makes use of voluntary efforts (ie, maximal voluntary contraction [MVC]), due to centrally mediated inhibition.5
Furthermore, the potential for aggravation of any damage to the musculoskeletal unit cannot be ruled out. Having
been developed over the last 15 years, tensiomyography (TMG) is a portable and noninvasive means of measuring
muscle response through combined use of submaximal (below voluntary maximal activation) electrical stimulus
and a digital displacement sensor,6–8 similar to that used in mechanomyography.9 TMG records spatial and temporal
parameters of the radial displacement of the muscle belly in response to electrical stimuli10 and is reliable within11
and between days.12 Furthermore, it has demonstrated good long-term stability after fatigue13 and has displayed
significant interclass correlation coefficient with decline and recovery of MVC after exercise-induced muscle
damage.14 In particular, muscle displacement (Dm) and contraction time (Tc) have shown greatest stability.12

Macgregor et al, 2016 – Reduced Radial Displacement of the Gastrocnemius Medialis Muscle After Electrically Elicited Fatigue